Abstract
The aim of this study was to assess and monitor airway exhalation and deposition of particulate matter (PM). After standardizing inspiratory/expiratory flow and volumes, a novel device was tested on a group of 20 volunteers and in a field study on workers exposed to cristobalite. Both male and female subjects showed a higher percentage of deposition in the 0.5 μm channel than in the 0.3 μm channel on a laser particle counter, but it was higher in the males because of their higher exhaled lung volumes. The device was tested on a wider range of particles (0.3–0.5–1.0–2.5 μm) in the cristobalite productive division. The device has low intrasubject variability and good reproducibility, with geometric mean of %CV < 5%. Such a measure can be used to assess individual susceptibility to PM, making repeated measures in different environments, and examining the persistence of particles in the airways after a period in polluted environments.
Acknowledgements
The study was supported by the Italian Ministry of Education, University and Research (Strategic Program of Ricerca Finalizzata PMS/40/06, RFPS-2006-4-335269). We would thank Dr Marina Corti and Petra Gergelova for their contribution to subject enrolment.
Declaration of interest: The device described in this paper has a patent pending in Italy (no. RM2008A000525) submitted by A.M. and M.G. on behalf of the National Institute of Occupational Safety and Health (ISPESL).